1. Field of the Invention
The present invention relates generally to computer networks, and more specifically to the scalability of a multiple server environment hosted on a mainframe computer.
2. Background of the Invention
As traffic on computer networks increases, the demand placed on servers often causes these servers to become overloaded. This is particularly true for web servers. One solution to the problem of increased server loads is to upgrade the individual servers. However, the upgrade process is complex and expensive, and may need to be performed repeatedly if the workload continues to increase.
A better solution is the multi-server approach, in which network requests come to a single address and are redirected to a cluster of servers. Each server then handles only a portion of the requests that come to the specified network address. When load increases, new servers can be added to the cluster to handle the increased workload.
It is now possible to host these servers on a single mainframe computer. Each server has its own independent operating system running on the mainframe. Hosting these virtual servers on the mainframe results in lower operating costs because less power, physical space, and trained personnel are required to maintain them.
However, the virtual servers become system bound when the service requests exceed the service capacity of the virtual server. The interrupt handler that services external requests is unable to process user requests in a responsive manner, and queues build up in the system. At this point, the server resource becomes effectively unavailable to the end users. Until the existing processes are complete, the application hosted on the virtual servers is unable to accommodate new service requests, and performance declines, sometimes drastically.
Currently, it is necessary for a qualified technician to spend hours to create a new virtual server (and operating system). Therefore, it would be desirable to have a method for quickly and efficiently instantiating new virtual servers, and then using those servers to aid in handling the increased workload.